3 files changed, 68 insertions, 77 deletions

diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index 88dafdf45c4..ab324d984b8 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -185,11 +185,19 @@ iscsi_hdr_extract(struct iscsi_tcp_conn *tcp_conn)
  * must be called with session lock
  */
 static void
-__iscsi_ctask_cleanup(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
+iscsi_tcp_cleanup_ctask(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
 {
 	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
+	struct iscsi_r2t_info *r2t;
 	struct scsi_cmnd *sc;
 
+	/* flush ctask's r2t queues */
+	while (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*))) {
+		__kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
+			    sizeof(void*));
+		debug_scsi("iscsi_tcp_cleanup_ctask pending r2t dropped\n");
+	}
+
 	sc = ctask->sc;
 	if (unlikely(!sc))
 		return;
@@ -374,6 +382,7 @@ iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
 		spin_unlock(&session->lock);
 		return 0;
 	}
+
 	rc = __kfifo_get(tcp_ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
 	BUG_ON(!rc);
 
@@ -399,7 +408,7 @@ iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
 	tcp_ctask->exp_r2tsn = r2tsn + 1;
 	tcp_ctask->xmstate |= XMSTATE_SOL_HDR;
 	__kfifo_put(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*));
-	__kfifo_put(conn->xmitqueue, (void*)&ctask, sizeof(void*));
+	list_move_tail(&ctask->running, &conn->xmitqueue);
 
 	scsi_queue_work(session->host, &conn->xmitwork);
 	conn->r2t_pdus_cnt++;
@@ -484,7 +493,7 @@ iscsi_tcp_hdr_recv(struct iscsi_conn *conn)
 			goto copy_hdr;
 
 		spin_lock(&session->lock);
-		__iscsi_ctask_cleanup(conn, tcp_conn->in.ctask);
+		iscsi_tcp_cleanup_ctask(conn, tcp_conn->in.ctask);
 		rc = __iscsi_complete_pdu(conn, hdr, NULL, 0);
 		spin_unlock(&session->lock);
 		break;
@@ -745,10 +754,11 @@ static int iscsi_scsi_data_in(struct iscsi_conn *conn)
 done:
 	/* check for non-exceptional status */
 	if (tcp_conn->in.hdr->flags & ISCSI_FLAG_DATA_STATUS) {
-		debug_scsi("done [sc %lx res %d itt 0x%x]\n",
-			   (long)sc, sc->result, ctask->itt);
+		debug_scsi("done [sc %lx res %d itt 0x%x flags 0x%x]\n",
+			   (long)sc, sc->result, ctask->itt,
+			   tcp_conn->in.hdr->flags);
 		spin_lock(&conn->session->lock);
-		__iscsi_ctask_cleanup(conn, ctask);
+		iscsi_tcp_cleanup_ctask(conn, ctask);
 		__iscsi_complete_pdu(conn, tcp_conn->in.hdr, NULL, 0);
 		spin_unlock(&conn->session->lock);
 	}
@@ -769,7 +779,7 @@ iscsi_data_recv(struct iscsi_conn *conn)
 		break;
 	case ISCSI_OP_SCSI_CMD_RSP:
 		spin_lock(&conn->session->lock);
-		__iscsi_ctask_cleanup(conn, tcp_conn->in.ctask);
+		iscsi_tcp_cleanup_ctask(conn, tcp_conn->in.ctask);
 		spin_unlock(&conn->session->lock);
 	case ISCSI_OP_TEXT_RSP:
 	case ISCSI_OP_LOGIN_RSP:
@@ -1308,7 +1318,7 @@ iscsi_tcp_cmd_init(struct iscsi_cmd_task *ctask)
 				    ctask->imm_count -
 				    ctask->unsol_count;
 
-		debug_scsi("cmd [itt %x total %d imm %d imm_data %d "
+		debug_scsi("cmd [itt 0x%x total %d imm %d imm_data %d "
 			   "r2t_data %d]\n",
 			   ctask->itt, ctask->total_length, ctask->imm_count,
 			   ctask->unsol_count, tcp_ctask->r2t_data_count);
@@ -1636,7 +1646,7 @@ handle_xmstate_sol_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
 	}
 solicit_again:
 	/*
-	 * send Data-Out whitnin this R2T sequence.
+	 * send Data-Out within this R2T sequence.
 	 */
 	if (!r2t->data_count)
 		goto data_out_done;
@@ -1731,7 +1741,7 @@ handle_xmstate_w_pad(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
 	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 	struct iscsi_data_task *dtask = tcp_ctask->dtask;
-	int sent, rc;
+	int sent = 0, rc;
 
 	tcp_ctask->xmstate &= ~XMSTATE_W_PAD;
 	iscsi_buf_init_iov(&tcp_ctask->sendbuf, (char*)&tcp_ctask->pad,
@@ -2002,20 +2012,6 @@ iscsi_tcp_conn_bind(struct iscsi_cls_session *cls_session,
 }
 
 static void
-iscsi_tcp_cleanup_ctask(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
-{
-	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
-	struct iscsi_r2t_info *r2t;
-
-	/* flush ctask's r2t queues */
-	while (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*)))
-		__kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
-			    sizeof(void*));
-
-	__iscsi_ctask_cleanup(conn, ctask);
-}
-
-static void
 iscsi_tcp_suspend_conn_rx(struct iscsi_conn *conn)
 {
 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
@@ -2057,6 +2053,7 @@ iscsi_tcp_mgmt_init(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask,
 	iscsi_buf_init_iov(&tcp_mtask->headbuf, (char*)mtask->hdr,
 			   sizeof(struct iscsi_hdr));
 	tcp_mtask->xmstate = XMSTATE_IMM_HDR;
+	tcp_mtask->sent = 0;
 
 	if (mtask->data_count)
 		iscsi_buf_init_iov(&tcp_mtask->sendbuf, (char*)mtask->data,
diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index 7e6e031cc41..1a8cd20f484 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -189,6 +189,7 @@ static void iscsi_complete_command(struct iscsi_session *session,
 {
 	struct scsi_cmnd *sc = ctask->sc;
 
+	ctask->state = ISCSI_TASK_COMPLETED;
 	ctask->sc = NULL;
 	list_del_init(&ctask->running);
 	__kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
@@ -568,20 +569,24 @@ static int iscsi_data_xmit(struct iscsi_conn *conn)
 	}
 
 	/* process command queue */
-	while (__kfifo_get(conn->xmitqueue, (void*)&conn->ctask,
-			   sizeof(void*))) {
+	spin_lock_bh(&conn->session->lock);
+	while (!list_empty(&conn->xmitqueue)) {
 		/*
 		 * iscsi tcp may readd the task to the xmitqueue to send
 		 * write data
 		 */
-		spin_lock_bh(&conn->session->lock);
-		if (list_empty(&conn->ctask->running))
-			list_add_tail(&conn->ctask->running, &conn->run_list);
+		conn->ctask = list_entry(conn->xmitqueue.next,
+					 struct iscsi_cmd_task, running);
+		conn->ctask->state = ISCSI_TASK_RUNNING;
+		list_move_tail(conn->xmitqueue.next, &conn->run_list);
 		spin_unlock_bh(&conn->session->lock);
+
 		rc = tt->xmit_cmd_task(conn, conn->ctask);
 		if (rc)
 			goto again;
+		spin_lock_bh(&conn->session->lock);
 	}
+	spin_unlock_bh(&conn->session->lock);
 	/* done with this ctask */
 	conn->ctask = NULL;
 
@@ -691,6 +696,7 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
 	sc->SCp.phase = session->age;
 	sc->SCp.ptr = (char *)ctask;
 
+	ctask->state = ISCSI_TASK_PENDING;
 	ctask->mtask = NULL;
 	ctask->conn = conn;
 	ctask->sc = sc;
@@ -700,7 +706,7 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
 
 	session->tt->init_cmd_task(ctask);
 
-	__kfifo_put(conn->xmitqueue, (void*)&ctask, sizeof(void*));
+	list_add_tail(&ctask->running, &conn->xmitqueue);
 	debug_scsi(
 	       "ctask enq [%s cid %d sc %lx itt 0x%x len %d cmdsn %d win %d]\n",
 		sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
@@ -977,31 +983,27 @@ static int iscsi_exec_abort_task(struct scsi_cmnd *sc,
 /*
  * xmit mutex and session lock must be held
  */
-#define iscsi_remove_task(tasktype)					\
-static struct iscsi_##tasktype *					\
-iscsi_remove_##tasktype(struct kfifo *fifo, uint32_t itt)		\
-{									\
-	int i, nr_tasks = __kfifo_len(fifo) / sizeof(void*);		\
-	struct iscsi_##tasktype *task;					\
-									\
-	debug_scsi("searching %d tasks\n", nr_tasks);			\
-									\
-	for (i = 0; i < nr_tasks; i++) {				\
-		__kfifo_get(fifo, (void*)&task, sizeof(void*));		\
-		debug_scsi("check task %u\n", task->itt);		\
-									\
-		if (task->itt == itt) {					\
-			debug_scsi("matched task\n");			\
-			return task;					\
-		}							\
-									\
-		__kfifo_put(fifo, (void*)&task, sizeof(void*));		\
-	}								\
-	return NULL;							\
-}
+static struct iscsi_mgmt_task *
+iscsi_remove_mgmt_task(struct kfifo *fifo, uint32_t itt)
+{
+	int i, nr_tasks = __kfifo_len(fifo) / sizeof(void*);
+	struct iscsi_mgmt_task *task;
+
+	debug_scsi("searching %d tasks\n", nr_tasks);
+
+	for (i = 0; i < nr_tasks; i++) {
+		__kfifo_get(fifo, (void*)&task, sizeof(void*));
+		debug_scsi("check task %u\n", task->itt);
+
+		if (task->itt == itt) {
+			debug_scsi("matched task\n");
+			return task;
+		}
 
-iscsi_remove_task(mgmt_task);
-iscsi_remove_task(cmd_task);
+		__kfifo_put(fifo, (void*)&task, sizeof(void*));
+	}
+	return NULL;
+}
 
 static int iscsi_ctask_mtask_cleanup(struct iscsi_cmd_task *ctask)
 {
@@ -1043,7 +1045,6 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
 	struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
 	struct iscsi_conn *conn = ctask->conn;
 	struct iscsi_session *session = conn->session;
-	struct iscsi_cmd_task *pending_ctask;
 	int rc;
 
 	conn->eh_abort_cnt++;
@@ -1071,17 +1072,8 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
 		goto failed;
 	}
 
-	/* check for the easy pending cmd abort */
-	pending_ctask = iscsi_remove_cmd_task(conn->xmitqueue, ctask->itt);
-	if (pending_ctask) {
-		/* iscsi_tcp queues write transfers on the xmitqueue */
-		if (list_empty(&pending_ctask->running)) {
-			debug_scsi("found pending task\n");
-			goto success;
-		} else
-			__kfifo_put(conn->xmitqueue, (void*)&pending_ctask,
-				    sizeof(void*));
-	}
+	if (ctask->state == ISCSI_TASK_PENDING)
+		goto success;
 
 	conn->tmabort_state = TMABORT_INITIAL;
 
@@ -1263,6 +1255,7 @@ iscsi_session_setup(struct iscsi_transport *iscsit,
 		if (cmd_task_size)
 			ctask->dd_data = &ctask[1];
 		ctask->itt = cmd_i;
+		INIT_LIST_HEAD(&ctask->running);
 	}
 
 	spin_lock_init(&session->lock);
@@ -1282,6 +1275,7 @@ iscsi_session_setup(struct iscsi_transport *iscsit,
 		if (mgmt_task_size)
 			mtask->dd_data = &mtask[1];
 		mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
+		INIT_LIST_HEAD(&mtask->running);
 	}
 
 	if (scsi_add_host(shost, NULL))
@@ -1361,12 +1355,7 @@ iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
 	conn->tmabort_state = TMABORT_INITIAL;
 	INIT_LIST_HEAD(&conn->run_list);
 	INIT_LIST_HEAD(&conn->mgmt_run_list);
-
-	/* initialize general xmit PDU commands queue */
-	conn->xmitqueue = kfifo_alloc(session->cmds_max * sizeof(void*),
-					GFP_KERNEL, NULL);
-	if (conn->xmitqueue == ERR_PTR(-ENOMEM))
-		goto xmitqueue_alloc_fail;
+	INIT_LIST_HEAD(&conn->xmitqueue);
 
 	/* initialize general immediate & non-immediate PDU commands queue */
 	conn->immqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
@@ -1410,8 +1399,6 @@ login_mtask_alloc_fail:
 mgmtqueue_alloc_fail:
 	kfifo_free(conn->immqueue);
 immqueue_alloc_fail:
-	kfifo_free(conn->xmitqueue);
-xmitqueue_alloc_fail:
 	iscsi_destroy_conn(cls_conn);
 	return NULL;
 }
@@ -1489,7 +1476,6 @@ void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
 		session->cmdsn = session->max_cmdsn = session->exp_cmdsn = 1;
 	spin_unlock_bh(&session->lock);
 
-	kfifo_free(conn->xmitqueue);
 	kfifo_free(conn->immqueue);
 	kfifo_free(conn->mgmtqueue);
 
@@ -1572,7 +1558,7 @@ static void fail_all_commands(struct iscsi_conn *conn)
 	struct iscsi_cmd_task *ctask, *tmp;
 
 	/* flush pending */
-	while (__kfifo_get(conn->xmitqueue, (void*)&ctask, sizeof(void*))) {
+	list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
 		debug_scsi("failing pending sc %p itt 0x%x\n", ctask->sc,
 			   ctask->itt);
 		fail_command(conn, ctask, DID_BUS_BUSY << 16);
diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h
index ba2760802de..e71d6e96eca 100644
--- a/include/scsi/libiscsi.h
+++ b/include/scsi/libiscsi.h
@@ -83,6 +83,12 @@ struct iscsi_mgmt_task {
 	struct list_head	running;
 };
 
+enum {
+	ISCSI_TASK_COMPLETED,
+	ISCSI_TASK_PENDING,
+	ISCSI_TASK_RUNNING,
+};
+
 struct iscsi_cmd_task {
 	/*
 	 * Becuae LLDs allocate their hdr differently, this is a pointer to
@@ -101,6 +107,8 @@ struct iscsi_cmd_task {
 	struct iscsi_conn	*conn;		/* used connection    */
 	struct iscsi_mgmt_task	*mtask;		/* tmf mtask in progr */
 
+	/* state set/tested under session->lock */
+	int			state;
 	struct list_head	running;	/* running cmd list */
 	void			*dd_data;	/* driver/transport data */
 };
@@ -134,7 +142,7 @@ struct iscsi_conn {
 	struct kfifo		*immqueue;	/* immediate xmit queue */
 	struct kfifo		*mgmtqueue;	/* mgmt (control) xmit queue */
 	struct list_head	mgmt_run_list;	/* list of control tasks */
-	struct kfifo		*xmitqueue;	/* data-path cmd queue */
+	struct list_head	xmitqueue;	/* data-path cmd queue */
 	struct list_head	run_list;	/* list of cmds in progress */
 	struct work_struct	xmitwork;	/* per-conn. xmit workqueue */
 	/*